Goods which are transported via intermodal shipping containers need to be monitored for the security of the container, the location of the container, and the environmental status of the goods. Mechanical security seals on container doors can be tampered and restored or replaced to approximate condition so as to pass a casual inspection, so that pilfered or tampered goods are not discovered until the container is opened at the destination. Conventional electronic security seals (e-Seals) improve upon mechanical seals, as they can provide a wireless report of a security tamper. e-Seals are limited by a need for external power such as from the cab of a truck, which is not available for other intermodal transport such as trains, barges or ships. Power consumption limits battery powered e-Seals to infrequent location and reporting updates. Environmental monitoring of the container goods can be performed using chart recorders inside the container, which do not provide real-time knowledge of temperature, humidity or shock damage to the goods until the container is opened at the destination. The practical use of conventional e-Seals is limited by the high cost of such devices.